The present invention relates generally to the automatic identification of rail cars, and more specifically to an integrated identification module and terminal block for rail cars equipped with electro-pneumatic brakes.
With the addition of electro-pneumatically operated train brakes to railway freight cars, comes a need to be able to automatically identify the types, weights and braking ratios of the individual cars in the train. Present systems address this by requiring that serial numbers of the cars as well as other related information be entered into a data file in the locomotive controller. This method does provide the information necessary to properly identify each car in the train; however, it is very time consuming when dealing with long trains (for example, one hundred cars or more), and must be manually updated every time a train adds or drops off cars or locomotives. Moreover, manually entering the data increases the opportunity for error.
A system for automatic identification of railcars is disclosed in U.S. Pat. No. 5,967,465 to Lumbis, et al. Lumbis '465 discloses an automatic identification of EP braked equipped railcars having a storage device or ID module permanently mounted on the car, including the car identification data. The prior art ID module is connected to the local communication node, which communicates with the locomotive and a network for reading the identification data stored in the storage device. The local communication node then communicates the identification data to a controller at the locomotive. Preferably, the ID module is a subsidiary communication node controlled by the local communication node and activated by the local communication node when it requires information. Lumbis also shows a terminal block for connecting the local node and current sensor separate from the ID module, and interconnected by wires.
The presently configured integrated identification module for ECP brake applications improves upon the prior art as disclosed in '465 by integrating the wires, terminal block, and ID module into a common housing.
The novel arrangement of the terminals, housing, and a circuit module comprising sensors, wires, and a circuit board simplifies the electric connection, and further provides a more durable, solid-state arrangement that reduces the risk of failure. Additionally, the arrangement simplifies the process of testing the brake and communication systems by allowing an operator to electrically isolate the electronics and/or the car control device without physically removing leads from the terminals.
The present ID module is for use in a train that includes at least one locomotive and a plurality of cars, each car being serially connected into a network by a power and communication trainline to an adjacent car. Each car is equipped with a local communication node connected to a car control device and to the network.
The invention comprises a common housing, preferably made of a nonconductive material. A circuit module is enclosed within the housing and includes a second communication node and a current sensor. A terminal block is formed on the housing, and a plurality of stud terminals extend through apertures in the terminal block such that a first end of each stud terminal is outside the housing and a second end of each stud terminal is inside the housing. Selected stud terminals contact the circuit module at their respective second ends.
At least two input leads comprising an input from a power and communication trainline are connected to the first end of selected stud terminals such that each input lead from the trainline is connected to its own stud terminal. An equal number of electrical output leads comprising an output of the power and communication trainline are connected to the first ends of another set of selected stud terminals such that each output electrical lead to the trainline extends from the first end of its own stud terminal.
A jumper wire in the circuit module passes through the current sensor and interconnects the second ends of a selected input power and communication trainline lead to a selected power and communication trainline output lead.
A shield input from the power and communication trainline is connected to the first end of a distinct, selected terminal; a shield output from the power and communication trainline is connected to the first end of another distinct stud terminal. These two selected shield terminals are connected at their first ends by a conductive strip. Preferably, the second end of at least one of these shield terminals is connected to the ground of the circuit module.
The power and communication trainline preferably comprises two power carrying lines and at least one shield line. Thus, a total of at least three input terminals is needed. As mentioned earlier, one set of power and input communication trainline terminals are electrically connected by a jumper wire extending inside the housing. The other pair of stud terminals is connected at the first ends by a conductive strip. In order to make this discourse easier to follow, the terminals will be given numbers. The first pair of terminals, which connect the input and output leads from one line of the power and communication trainline, shall be labeled the first and second terminals. The second pair of terminals, which are connected at their second ends by the jumper wire, and which connect input and output leads from a second line from the power and communication trainline, will be called the third and fourth terminals. In like manner, the terminals receiving the shield input and output will be called the fifth and sixth terminals, respectively
The terminal block further includes seventh, eighth, ninth, and tenth stud terminals. The seventh and eighth terminals have second ends connected to supply input ports of the circuit module. Leads connect the first ends of the seventh and eighth stud terminals to supply output ports of the car control device. The ninth and tenth stud terminals are connected inside the housing by their second ends to communication ports of the circuit module. Leads connect the first ends of the ninth and tenth stud terminals to the communication ports of the car control device.
The housing includes eleventh and twelfth stud terminals, each connected at their second ends in series with a load and a switch. The first ends of the eleventh and twelfth stud terminals are connected to the first ends of one of the first and second stud terminals, and one of the third and fourth stud terminals, respectively; and the second communication node controls the switch.
The terminal block has first, second and third channels wherein the apertures for the terminals are formed in each of the channels. The first ends of first, second, and eleventh terminals are spaced apart in the first channel. A first conductive strip lies in the first channel to electrically connect the first ends of the first, second and eleventh termninals.
The first ends of the fifth and sixth terminals are spaced apart in the second channel; a second conductive strip lies in the second channel to electrically connect the first ends of the fifth and sixth terminals.
The first ends of the third, twelfth, and fourth terminals are spaced apart in the third channel. A third conductive strip lies in the channel to electrically connect the first ends of the third and twelfth terminals. A dividing structure lies in the third channel between the twelfth and fourth terminals in order to prevent the third conductive strip from creating electrical contact between the first ends of the fourth and twelfth terminals.
The car control device must also be in electric communication with the power and communication trainline. In that regard, at least two leads connect power and communication trainline ports of the car control device to the first end of one of the first and second stud terminals and one of the third and fourth stud terminals, respectively.
The circuit module includes electronics mounted to a circuit board, which is displaced from the housing and mounted to the second ends of a plurality of the stud terminals. A space is thereby formed between the circuit board and the housing. Preferably, the space between the circuit board and the housing and the circuit board is potted. The current sensor is mounted to the circuit board and is potted.
Each of the terminals may be threaded to receive a cap. The cap on each of the eleventh and twelfth terminals, however, is a specially designed electrically-conducting connector cap. Each electrically-conducting connector cap has an engaging section that threadedly engages a portion of the first end of each of the eleventh and twelfth terminals, and an extending section extending from the engaging section toward the conducting strip. The connector cap on the eleventh terminal is threadedly adjustable between a connected position, wherein the extending contacts the first conducting strip, and a disconnected position wherein the extending section does not contact the first conducting strip. Likewise, the connector cap on the twelfth terminal is threadedly adjustable between a connected position wherein the extending section contacts the third conducting strip, and a disconnected position wherein the extending section does not contact the first conducting strip. This structure allows electrical isolation without physical disconnection of the trainline leads.
Preferably, the second ends of terminals five through ten are electrically affixed to the circuit board. This attachment may be accomplished either by electrically conductive bolts or by soldering. In contrast, the second ends of terminals eleven and twelve are electrically connected to the circuit board by an electrical lead extending from the circuit board to the second end of the respective terminal. Moreover, the second ends of terminals one through four do not make electrical contact with the circuit board.
There are two distinct embodiments for attachment of the jumper wire to the second end of the second and fourth terminals. In a first embodiment, terminals one through four are bolted to the circuit board. The jumper wire is electrically connected to the second ends of termninals two and four by bolts which create mechanical but not electrical contact with the circuit board. The jumper wire passes through the current sensor between the two bolted ends.
In a second embodiment, the second ends of terminals two and four extend through apertures in the circuit board. Bolts engage an internally threaded portion of the second end of each of the second and fourth terminals to attach jumper wire. The apertures in the circuit module are formed significantly large to prevent contact between the terminals and the circuit board. Any open space inside the housing is preferably filled by potting.
The second embodiment is preferred because the ID module may be exposed to extreme heat and cold as the train travels through various climates. Consequently, the materials will naturally expand and contract. In order to prevent material failure due to the strains and stresses of expansion, the apertures allow the board to expand or contract more freely.
The housing is preferably bolted to a junction box.
All told, three pair of leads extend from the terminals to the car control device. These leads are formed into a single cable that terminates with a six-prong, military style plug. The plug connects to a female plugs that leads to the car control device. Thus, the car control device may be disconnected from the power and communication trainline by removing the connection between these mating plugs
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.